Vaughn’s attorneys objected to questions prosecutors asked Illinois State Police Sgt. Gary Lawson about limitations Vaughn allegedly placed on his interviews with investigators after his family was killed in June 2007. They said the question was leading, and beyond the scope of their initial questioning of Lawson.

“It’s a big issue,” Lenard said of the question asked by Assistant States Attorney Chris Regis. “He asked a leading question.”

Judge Daniel Rozak sustained their objection, but then rejected their request for a mistrial.

When jurors were brought back to the courtroom, testimony continued with Vaughn’s sister-in-law, Rachel Vaughn, taking the stand. Rachel Vaughn testified about a conversation she had with Kimberly Vaughn about two weeks before Kimberly and her children were found shot to death in the family’s SUV.

During that conversation, Rachel Vaughn said Kimberly discussed being anxious, and pointed to migraine and blood pressure medicine that she was taking as being a possible catalyst for her increasing anxiety.

Rachel Vaughn also testified that during their conversation, Kimberly told her that online classes she was taking at the University of Phoenix had recently taken a toll on her mental state. In reference to a homework assignment she almost failed to turn in, Rachel said Kimberly told her that she "freaked out."

"Her words were that she panicked and made a big scene," Rachel Vaughn said. Kimberly and Christopher Vaughn were at a Jeep Jamboree in Missouri where she could not access the Internet to turn in her work.

Kimberly "said she had a lot of trouble with anxiety. Part of reason she was telling me that story is she was embarrassed by her reaction. She said she knew she had overreacted, and she was overreacting to small provocation and that was something she was working with her doctor."

Defense attorneys for Christopher Vaughn have said Kimberly was suicidal, and turned the gun on herself, her husband and her children as a result. After the judge sent the jurors home for the day Thursday, lawyers found themselves arguing about whether Kimberly Vaughn’s doctors can testify she thought her sister was bi-polar. The judge said it can only come up so defense attorneys could argue to the jury about her state of mind when she died.

Prosecutors allege Christopher Vaughn wanted to escape a life of suburban obligation and head to the Canadian wilderness, so he shot Kimberly and their three children -- 12-year-old Abigayle, 11-year-old Cassandra and 8-year-old Blake -- on June 14, 2007. They say he then shot himself twice, creating superficial wounds in his wrist and thigh, before flagging down a passerby on a frontage road west of Interstate 55, where the SUV was found.

Vaughn contends he was taking his family to a water park in Springfield, but pulled off the highway when his wife got sick. He said he sought a secluded area to give Kimberly some privacy. He said he got out of the car, checked the rooftop luggage carrier and returned to the driver’s seat. That’s when he said his wife shot him and he left the SUV.

Prosecutors said Vaughn got out of the car, shot his wife and children, and then returned to the driver’s seat to shoot himself so it would look like his wife turned the gun on him. Then they said he put his 9 mm Taurus pistol on the floor between Kimberly’s feet and unbuckled her seat belt.

A bloodstain pattern analyst has said Christopher Vaughn’s blood was found on Kimberly’s retracted seatbelt, on the car’s center console and on the floor beside the gun. Her blood was also found on his jacket, which prosecutors say disproves Vaughn’s statement that he was out of the vehicle when his family was shot.